linux-kernel - Re: [PATCH v4 0/2] Enable JPEG encoding on rk3588

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Date: Mon, 29 Apr 2024 01:29:19 +0800
From: Jianfeng Liu <liujianfeng1994@...il.com>
To: heiko@...ech.de
Cc: andy.yan@...k-chips.com,
	conor+dt@...nel.org,
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Subject: Re: [PATCH v4 0/2] Enable JPEG encoding on rk3588

Hi Heiko,

On Sun, 28 Apr 2024 19:01:38 +0200, Heiko Stübner wrote:
>the basic problem is that exposing multiple jpeg encoders would require
>userspace to do the scheduling. Which is bad.
>I.e. all userspace programms would need to know the existence of
>all jpeg encoders and then somehow negotiate how to use all of them
>most efficiently.
>
>Think multiple different programs that would need to negotiate to
>spread across all of them in the best way.
>
>Doing this in the kernel, we just expose one encoder (and queue) all
>programs would just pile onto that one encoder and the kernel then
>would be on the hook to do the scheduling - which the kernel can do
>better (with relevant code implemented)

Yeah let kernel do the scheduling is indeed better. And I'm happy to
hear this method.

So I will keep the vpu at feb50000 with jpeg endoder disabled until
multi encoder scheduling is implemented.

Best regards,
Jianfeng